1. Field of the Invention
The present invention relates to a knife for cutting a packaging material. More specifically, the present invention relates to a knife for partially cutting a carton blank, and the blank produced therefrom.
2. Description of the Related Art
Gable top cartons have long been the preferred package for milk and milk related products. These well-known cartons are usually fabricated from a blank composed of a paperboard substrate coated with a thermoplastic material on both the interior and exterior surfaces. The thermoplastic material, usually low density polyethylene, has many functions including preventing the product from contacting the paperboard substrate. To fabricate a blank, a large web of coated paperboard is printed upon, scored to create the crease or fold lines, and then cut into the individual carton blanks. The blanks are then fed into a packaging machine and formed, filled and sealed to create the finished product.
Recently, gable top cartons have assumed a new role as the preferred package for juices, particularly orange juice. The consumers preference for gable top cartons is at least partially generated by the perception of freshness associated with the gable top carton. The opposing top panels meeting to form the gable top with a top fin creates an image of a fresh, healthy product contained within the carton. The only detraction from this image was the lack of a tight reseal of the carton after the initial opening of the carton by a consumer. The integrated closure formed from the side of the top of the carton allowed for good pourability, however, the resealing was adequate at best.
This minor detraction was alleviated with the introduction of plastic fitments applied to the gable top cartons. The fitments, which generally include a spout with a flange and a cap, allowed for a tight reseal of the carton after the initial opening. The use of fitments on cartons further enhanced the consumer's perception that gable top cartons contained fresh and healthy products.
In the rush to meet the consumer's demand, the packaging industry developed new packaging/filling machines that applied a fitment to cartons prior to sterilization or filling. The demand to have packaging machines with the smallest "footprint" (the area of the machine) in a dairy meant that most older machines did not have sufficient space within the machine to incorporate a fitment applicator. This rendered older machines without the ability to provide a carton with a fitment thereby reducing their value to the dairy or like facility. Thus a need to apply a fitment on a formed, filled and sealed carton grew throughout the packaging industry.
Another problem necessitating the need to apply a fitment on a formed, filled and sealed carton pertains to maintaining a sterile environment within a form, fill and seal packaging machine to produce an extended shelf life ("ESL") product, a high acid ambient distribution ("HAAD") product, or an aseptic product. The ESL product allows for a product to have double or triple the refrigerated shelf life of a non-ESL product. The HAAD product allows for a high acid (pH&lt;4.5) product such as orange juice to be stored unrefrigerated for an extended time period. The aseptic product allows for any product to be stored unrefrigerated for an extended time period. All of these products need to be produced in a sterile, contaminant-free environment.
Thus, the packaging industry created a need to apply a fitment to a formed, filled and sealed carton. This created a need for a package that could be utilized with a fitment applied to a formed, filled and sealed carton since in-line fitment applicators would apply the fitment through a pre-incised aperture in the carton prior to filling or sterilization. Thus, a need was created for a carton that could be accessed with a post-processing applied fitment while still providing the necessary protection to the product contained therein until the initial opening of the carton by a consumer. This further created a need to produce a blank for fabrication into a carton for application of a fitment thereon after processing into a formed, filled and sealed carton.